The invention relates to a manipulatable read-only memory, in particular a punched card read device, with conductor paths, i.e. row conductors and column conductors disposed in a matrix formation in the manner of a cross-bar distributor, wherein each row conductor intersects each column conductor at an intersection point, in the vicinity of which the two conductors are connected to one another over a photo-resistor and a rectifier containing a blocking contact, which are disposed in series with one another.
Memories of this type are known in various embodiments, for example in German AS 1 2 66 353 or BBC Information Edition 49, 1967, pages 541-547. Such type of stores have a number of advantages in comparison to conventional cross-bar distributors which employ electro-mechanical switches, among which are reliability of operation, maintenance of small dimensions (thin film technique) and enable a change in programming (manipulation) by a simple exchanging of the mask. However, they are comparatively expensive to produce as the (vacuum) vapor deposition of thin layers necessitates a sequence of operational steps which must be very carefully effected and matched to one another.